Please study official Domain Name Mapping protocol: http://tools.ietf.org/html/rfc5731

More info at http://en.wikipedia.org/wiki/Extensible_Provisioning_Protocol

Domain name mapping protocol short version:

Domain create

Field name                 Min-max  Field description
-------------------------  -------  -----------------
<create>                   1       
  <domain:create>          1        Attribute: xmlns:domain="https://epp.tld.ee/schema/domain-eis-1.0.xsd"
    <domain:name>          1        Domain name. Can contain unicode characters.
    <domain:period>        0-1      Registration period for domain. 
                                    Must add up to 3m, 6m, 9m, 1y, 2y, 3y, 4y, 5y, 6y, 7y, 8y, 9y, 10y.
                                    Attribute: unit="y/m/d"
                                    Default is 1 year.
    <domain:ns>            0-1       
      <domain:hostAttr>    2-11    
        <domain:hostName>  1        Hostname of the nameserver
        <domain:hostAddr>  0-2      Required if nameserver is under domain zone. 
                                    Attribute ip="v4 / v6"
    <domain:registrant>    1        Contact reference to the registrant
    <domain:contact>       0-n      Contact reference. Admin contact is required if registrant is
                                    a juridical person. Attribute: type="admin / tech"
<extension>                1       
  <secDNS:create>          0-1      Attribute: xmlns:secDNS="urn:ietf:params:xml:ns:secDNS-1.1"
    <secDNS:keyData>       1-n     
      <secDNS:flags>       1        Allowed values: 0, 256, 257
      <secDNS:protocol>    1        Allowed values: 3
      <secDNS:alg>         1        Allowed values: 3, 5, 6, 7, 8, 10, 13, 14
      <secDNS:pubKey>      1        Public key
  <eis:extdata>            1        Attribute: xmlns:eis="https://epp.tld.ee/schema/eis-1.0.xsd"
    <eis:legalDocument>    1        Base64 encoded document. 
                                      Attribute: type="pdf/bdoc/ddoc/zip/rar/gz/tar/7z"
    <eis:reserved>         0-1
      <eis:pw>             0-1      Required if registering a reserved domain
<clTRID>                   0-1      Client transaction id

EXAMPLE REQUEST AND RESPONSE

Domain update

Field name                   Min-max   Field description
------------------------     --------  -----------------
<update>                     1        
  <domain:update>            1         Attribute: xmlns:domain="https://epp.tld.ee/schema/domain-eis-1.0.xsd"
    <domain:name>            1         Domain name. Can contain unicode characters.
    <domain:add>             0-1       Objects to add
      <domain:contact>       0-n       Contact reference. Attribute: type="admin / tech"
      <domain:status>        0-n       Status description. 
                                       Attribute: s="clientDeleteProhibited / clientHold / 
                                       clientRenewProhibited / clientTransferProhibited / 
                                       clientUpdateProhibited"
      <domain:ns>            0-1      
        <domain:hostAttr>    1        
          <domain:hostName>  1         Hostname of the nameserver
          <domain:hostAddr>  0-2       Required if nameserver is under domain zone. 
                                       Attribute ip="v4 / v6"
    <domain:rem>             0-1       Objects to remove
      <domain:contact>       0-n       Contact reference. Attribute: type="admin / tech"
      <domain:status>        0-n       Attribute: s="clientDeleteProhibited / clientHold / 
                                       clientRenewProhibited / clientTransferProhibited / 
                                       clientUpdateProhibited"
      <domain:ns>            0-1      
        <domain:hostAttr>    1        
          <domain:hostName>  1         Hostname of the nameserver
    <domain:chg>             0-1       Attributes to change
      <domain:registrant>    0-1       Contact reference to the registrant
                                         Optional attribute: verified="yes/no"
<extension>                  0-1       Required if registrant is changing
  <secDNS:update>            0-1       Attribute: xmlns:secDNS="urn:ietf:params:xml:ns:secDNS-1.1"
    <secDNS:rem>             0-1      
      <secDNS:keyData>       1-n      
        <secDNS:pubKey>      1         Public key
    <secDNS:add>             0-1      
      <secDNS:keyData>       1-n      
        <secDNS:flags>       1         Allowed values: 0, 256, 257
        <secDNS:protocol>    1         Allowed values: 3
        <secDNS:alg>         1         Allowed values: 3, 5, 6, 7, 8, 10, 13, 14
        <secDNS:pubKey>      1         Public key
  <eis:extdata>              0-1       Attribute: xmlns:eis="https://epp.tld.ee/schema/eis-1.0.xsd"
    <eis:legalDocument>      0-1       Base64 encoded document. Required if registrant is changing. 
                                         Attribute: type="pdf/bdoc/ddoc/zip/rar/gz/tar/7z"
<clTRID>                     0-1       Client transaction id

EXAMPLE REQUEST AND RESPONSE

Domain delete

Field name               Min-max  Field description
-----------------------  -------  -----------------
<delete>                 1       
  <domain:delete>        1        Attribute: xmlns:domain="https://epp.tld.ee/schema/domain-eis-1.0.xsd"
                                    Optional attribute: verified="yes/no"
    <domain:name>        1        Domain name. Can contain unicode characters.
<extension>              1       
  <eis:extdata>          1        Attribute: xmlns:eis="https://epp.tld.ee/schema/eis-1.0.xsd"
    <eis:legalDocument>  1        Base64 encoded document. 
                                    Attribute: type="pdf/bdoc/ddoc/zip/rar/gz/tar/7z"
<clTRID>                 0-1      Client transaction id

EXAMPLE REQUEST AND RESPONSE

Domain info

Field name               Min-max  Field description
-----------------------  -------  -----------------
<info>                   1       
  <domain:info>          1        Attribute: xmlns:domain="https://epp.tld.ee/schema/domain-eis-1.0.xsd"
    <domain:name>        1        Domain name. Can contain unicode characters. 
                                  Attribute: hosts="all / del / sub / none"
    <domain:authInfo>    0-1      Required if registrar is not the owner of the domain.
      <domain:pw>        1        Domain password. Attribute: roid="String"
<clTRID>                 0-1      Client transaction id

EXAMPLE REQUEST AND RESPONSE

Domain renew

Field name               Min-max  Field description
-----------------------  -------  -----------------
<renew>                  1       
  <domain:renew>         1        Attribute: xmlns:domain="https://epp.tld.ee/schema/domain-eis-1.0.xsd"
    <domain:name>        1        Domain name. Can contain unicode characters. 
    <domain:curExpDate>  1        Current expiry date (ISO8601 format)
    <domain:period>      0-1      Registration period for domain. 
                                  Must add up to 3m, 6m, 9m, 1y, 2y, 3y, 4y, 5y, 6y, 7y, 8y, 9y, 10y.
                                    Attribute: unit="y/m/d"
                                  Default value is 1 year.
<extension>              0-1     
  <eis:extdata>          0-1      Attribute: xmlns:eis="https://epp.tld.ee/schema/eis-1.0.xsd"
    <eis:legalDocument>  0-1      Base64 encoded document. 
                                    Attribute: type="pdf/bdoc/ddoc/zip/rar/gz/tar/7z"
<clTRID>                 0-1      Client transaction id

EXAMPLE REQUEST AND RESPONSE

Domain transfer

Field name               Min-max  Field description
-----------------------  -------  -----------------
<transfer>               1        Attribute: op="request/query/approve/reject/cancel"
  <domain:transfer>      1        Attribute: xmlns:domain="https://epp.tld.ee/schema/domain-eis-1.0.xsd"
    <domain:name>        1        Domain name. Can contain unicode characters. 
    <domain:authInfo>    1       
      <domain:pw>        1        Domain password. Attribute: roid="String"
<extension>              0-1     
  <eis:extdata>          0-1      Attribute: xmlns:eis="https://epp.tld.ee/schema/eis-1.0.xsd"
    <eis:legalDocument>  0-1      Base64 encoded document.  
                                    Attribute: type="pdf/bdoc/ddoc/zip/rar/gz/tar/7z"
<clTRID>                 0-1      Client transaction id

EXAMPLE REQUEST AND RESPONSE

Domain check

Field name               Min-max  Field description
-----------------------  -------  -----------------
<check>                  1       
  <domain:check>         1        Attribute: xmlns:domain="https://epp.tld.ee/schema/domain-eis-1.0.xsd"
    <domain:name>        1        Domain name. Can contain unicode characters. 
<clTRID>                 0-1      Client transaction id

EXAMPLE REQUEST AND RESPONSE